回复：还是换工作的问题。 请各位老师看看--URGENT

Once your prospective employer has filed H-1b transfer, you may start working for new employer, even without a receipt.

If you choose an EAD, it takes more time, which is not recommended in your case.

In case your I-485 is approved while your H-1b is still pending, you're fine.
http://blog.wenxuecity.com/blogview.php?date=200709&postID=16851#LastActionRule